SOAD is not metal.

GET THE F*CK OUT OF HERE WITH THAT SHIT.

Slipknot is a joke. They're faggots. You want metal? Well then.

ATR is not bad.
Killswitch is not bad.
In Flames old is F*CKING awesome, newer shit, more mainstream. (Not trying to be a hipster, but listen to it, you'll know what I'm talking about.)
This Ending - Boss Metal.
Pantera - Boss Metal.
Metallica - Boss Thrash.
Amon Amarth - Boss Metal.
Diecast - Boss Metal.
Lamb of God - BOSS Metal.
Arch Enemy - They're not bad.
Dark Tranquility - Not bad.
Dethklok - (In all seriousness) Boss Metal.
Opeth - Extremely Boss metal.
Slayer - You've got to be kidding me. If this isn't in your metal collection, kill yourself.
Soilwork - Pretty good.
Black Dhalia Murder - Boss metal.
Through the eyes of the Dead - Boss Metal.

I listen to new stuffs all the time, more metal, more awesome.